Do you have any proof of rap/hip-hop being the most successful/profitable music ever? You may be right but I highly doubt that it has surpassed, or even approached rock & roll:
Do I have any concrete proof - of course not. There's more hip-hop / rap artist in general than any other genre to date (and hip-hop is still growing). I believe you're using Rock & Roll a bit loosely. Rock & Roll is a very "broad" category. I believe you're mixing other genres as well (such as Metal and Soft Rock). You could even argue "pop music" putting names like U2 out there. A lot of rap music is considered pop music as well, which opens a whole new can of worms.
In short, Rock & Roll is not really a specific genre, like Pop isn't. Rock & Roll and Pop are fathers to several other genres. Would it shock me if there was data that proved a specific genre (like soft rock) was more profitable historically than hip-hop? No it wouldn't, but my money says hip-hop given it's massive cult following worldwide
in addition to millions and millions of casual fans, would make the hip-hop music genre a tough cookie to surpass.
You're right about the freedom of religion thing. I guess I was a little off base there. Also, I had no idea it was only recently (1954) added. I guess my point is the whole censorship thing. Too many activists and lobbyist are putting their hands in places they shouldn't.